Shielded electromagnetic communication with functional components of a machine

ABSTRACT

A system of a machine is provided. The system having: a network of a plurality of sensing/control/identification devices distributed throughout the machine, at least one of the plurality of sensing/control/identification devices associated with at least one sub-system component of the machine and operable to communicate through a plurality of electromagnetic signals; shielding surrounding at least one of the sensing/control/identification devices to contain the electromagnetic signals proximate to the at least one sub-system component; and a remote processing unit operable to communicate with the network of the sensing/control/identification devices through the electromagnetic signals, wherein the at least one of the plurality of sensing/control/identification devices has internal memory independent of the remote processing unit, the internal memory having historical data corresponding to the least one sub-system component.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a continuation-in-part of U.S. patent applicationSer. No. 15/114,234 filed on Jul. 26, 2016, which is a U.S. NationalStage of Application No. PCT/US2015/016761 filed on Feb. 20, 2015, whichclaims the benefit of U.S. Provisional Patent Application No. 61/946,064filed on Feb. 28, 2014, the contents of each of these applications areincorporated herein by reference thereto.

BACKGROUND

This disclosure relates to electromagnetic communication, and moreparticularly to electromagnetic communication through functionalcomponents of a machine.

A gas turbine engine typically includes a fan section, a compressorsection, a combustor section and a turbine section. Air entering thecompressor section is compressed and delivered into the combustorsection where it is mixed with fuel and ignited to generate a high-speedexhaust gas flow. The high-speed exhaust gas flow expands through theturbine section to drive the compressor and the fan section. Thecompressor section typically includes low and high pressure compressors,and the turbine section includes low and high pressure turbines.

Detailed knowledge of gas turbine engine and other machinery operationfor control or health monitoring requires sensing systems that needinformation from locations that are sometimes difficult to access due tomoving parts, internal operating environment or machine configuration.The access limitations make wire routing bulky, expensive and vulnerableto interconnect failures. The sensor and interconnect operatingenvironments for desired sensor locations often exceed the capability ofthe interconnect systems. In some cases, cable cost, volume and weightexceed the desired limits for practical applications.

Application of electromagnetic sensor technologies to address the wiringconstraints faces the challenge of providing reliable communications ina potentially unknown environment with potential interference frominternal or external sources.

BRIEF DESCRIPTION

In an embodiment, a system of a machine is provided. The system having:a network of a plurality of sensing/control/identification devicesdistributed throughout the machine, at least one of the plurality ofsensing/control/identification devices associated with at least onesub-system component of the machine and operable to communicate througha plurality of electromagnetic signals; shielding surrounding at leastone of the sensing/control/identification devices to contain theelectromagnetic signals proximate to the at least one sub-systemcomponent; and a remote processing unit operable to communicate with thenetwork of the sensing/control/identification devices through theelectromagnetic signals, wherein the at least one of the plurality ofsensing/control/identification devices has internal memory independentof the remote processing unit, the internal memory having historicaldata corresponding to the least one sub-system component.

In addition to one or more of the features described above, or as analternative to any of the foregoing embodiments, the shielding mayfurther include a metal waveguide, wherein the thickness of the metal ofthe waveguide is greater than a skin depth of the metal of thewaveguide.

In addition to one or more of the features described above, or as analternative to any of the foregoing embodiments, the shielding may be aFaraday shield.

In addition to one or more of the features described above, or as analternative to any of the foregoing embodiments, the shielding mayprevent electromagnetic signals external to the network from reachingthe least one of the sensing/control/identification devices.

In addition to one or more of the features described above, or as analternative to any of the foregoing embodiments, the shielding may be ametal screen.

In addition to one or more of the features described above, or as analternative to any of the foregoing embodiments, the at least one of thesensing/control/identification devices may be a RFID tag powered by anEM transmitting source.

In addition to one or more of the features described above, or as analternative to any of the foregoing embodiments, the EM transmittingsource may be the remote processing unit.

In yet another embodiment, a system for a gas turbine engine isprovided, the system having: a network of a plurality ofsensing/control/identification devices distributed throughout the gasturbine engine, at least one of the sensing/control/identificationdevices associated with at least one sub-system component of the gasturbine engine and operable to communicate through a plurality ofelectromagnetic signals; and a remote processing unit operable tocommunicate with the network of the sensing/control/identificationdevices through the electromagnetic signals, wherein the at least one ofthe plurality of sensing/control/identification devices has internalmemory independent of the remote processing unit, the internal memoryhaving historical data corresponding to the least one sub-systemcomponent.

In addition to one or more of the features described above, or as analternative to any of the foregoing embodiments, the at least onesub-system component may be part of at least one of a fan section, acompressor section, a combustor section and a turbine section of the gasturbine engine, and the at least one sub-system component contains aparameter of interest to a control and health monitoring system, whereinthe parameter of interest may be one of a pressure, a temperature, aspeed, a position, vibration and proximity or any other relevantphysically measurable parameter that is stored in the internal memoryindependent of the remote processing unit.

In addition to one or more of the features described above, or as analternative to any of the foregoing embodiments, further embodiments mayinclude shielding surrounding the at least one of thesensing/control/identification devices to contain the electromagneticsignals proximate to the at least one sub-system component.

In addition to one or more of the features described above, or as analternative to any of the foregoing embodiments, the shielding may be ametal waveguide, wherein the thickness of the metal of the waveguide isgreater than a skin depth of the waveguide.

In addition to one or more of the features described above, or as analternative to any of the foregoing embodiments, the shielding mayprevent electromagnetic signals external to the network from reachingthe least one of the sensing/control/identification devices.

In addition to one or more of the features described above, or as analternative to any of the foregoing embodiments, the shielding may be ametal screen or a Faraday shield.

In addition to one or more of the features described above, or as analternative to any of the foregoing embodiments, the at least one of thesensing/control/identification devices may be a RFID tag powered by anEM transmitting source.

In addition to one or more of the features described above, or as analternative to any of the foregoing embodiments, the EM transmittingsource may be the remote processing unit.

A method of tracking data relevant to a component of a gas turbineengine is also provided. The method including the steps of: securing asensing/control/identification device to a sub-system component of thegas turbine engine; shielding the sensing/control/identification devicefrom external electromagnetic signals proximate to the sub-systemcomponent; storing data relevant to the sub-system component in memoryof the sensing/control/identification device; and transmitting the datato a remote processing unit via electromagnetic signals through awaveguide.

In addition to one or more of the features described above, or as analternative to any of the foregoing embodiments, the communication pathcomprises a waveguide.

In addition to one or more of the features described above, or as analternative to any of the foregoing embodiments, the sub-systemcomponent may be part of at least one of a fan section, a compressorsection, a combustor section and a turbine section of the gas turbineengine, and the sub-system component contains a parameter of interest toa control and health monitoring system comprising the remote processingunit, wherein the parameter of interest may be one of a pressure, atemperature, a speed, a position, vibration and proximity or any otherrelevant physically measurable parameter that is stored in the memory ofthe sensing/control/identification device.

In addition to one or more of the features described above, or as analternative to any of the foregoing embodiments, thesensing/control/identification device may be a RFID tag powered by an EMtransmitting source.

In addition to one or more of the features described above, or as analternative to any of the foregoing embodiments, the EM transmittingsource is the remote processing unit.

A technical effect of the apparatus, systems and methods is achieved byelectromagnetic communication through functional components of a machineas described herein.

BRIEF DESCRIPTION OF THE DRAWINGS

The subject matter which is regarded as the present disclosure isparticularly pointed out and distinctly claimed in the claims at theconclusion of the specification. The foregoing and other features, andadvantages of the present disclosure are apparent from the followingdetailed description taken in conjunction with the accompanying drawingsin which:

FIG. 1 is a cross-sectional view of a gas turbine engine;

FIG. 2 is a schematic view of an example control and health monitoringsystem including a shielded electromagnetic network in accordance withan embodiment of the disclosure;

FIG. 3 is a schematic view of a communication path through a componentin accordance with an embodiment of the disclosure;

FIG. 4 is a schematic view of a waveguide in accordance with anembodiment of the disclosure;

FIG. 5 is a schematic view of another waveguide in accordance with anembodiment of the disclosure; and

FIG. 6 is schematic illustration of a portion of the shieldedelectromagnetic network in accordance with an embodiment of thedisclosure.

DETAILED DESCRIPTION

Various embodiments of the present disclosure are related toelectromagnetic communication in a machine. FIG. 1 schematicallyillustrates a gas turbine engine 20 as one example of a machine asfurther described herein. The gas turbine engine 20 is depicted as atwo-spool turbofan that generally incorporates a fan section 22, acompressor section 24, a combustor section 26 and a turbine section 28.Alternative engines may include an augmentor section (not shown) amongother systems or features. The fan section 22 drives air along a bypassflow path B in a bypass duct to provide a majority of the thrust, whilethe compressor section 24 drives air along a core flow path C forcompression and communication into the combustor section 26 thenexpansion through the turbine section 28. Although depicted as atwo-spool turbofan gas turbine engine in the disclosed non-limitingembodiment, it should be understood that the concepts described hereinare not limited to use with two-spool turbofans as the teachings may beapplied to other types of turbine engines including three-spoolarchitectures or any other machine that requires sensors to operate withsimilar environmental challenges or constraints. Additionally, theconcepts described herein may be applied to any machine or systemcomprised of control and/or health monitoring systems.

The exemplary engine 20 generally includes a low speed spool 30 and ahigh speed spool 32 mounted for rotation about an engine centrallongitudinal axis A relative to an engine static structure 36 viaseveral bearing systems 38. It should be understood that various bearingsystems 38 at various locations may alternatively or additionally beprovided, and the location of bearing systems 38 may be varied asappropriate to the application.

The low speed spool 30 generally includes an inner shaft 40 thatinterconnects a fan 42, a first (or low) pressure compressor 44 and afirst (or low) pressure turbine 46. The inner shaft 40 is connected tothe fan 42 through a speed change mechanism, which in exemplary gasturbine engine 20 is illustrated as a geared architecture 48 to drivethe fan 42 at a lower speed than the low speed spool 30. The high speedspool 32 includes an outer shaft 50 that interconnects a second (orhigh) pressure compressor 52 and a second (or high) pressure turbine 54.A combustor 56 is arranged in exemplary gas turbine engine 20 betweenthe high pressure compressor 52 and the high pressure turbine 54. Amid-turbine frame 58 of the engine static structure 36 is arrangedgenerally between the high pressure turbine 54 and the low pressureturbine 46. The mid-turbine frame 58 further supports bearing systems 38in the turbine section 28. The inner shaft 40 and the outer shaft 50 areconcentric and rotate via bearing systems 38 about the engine centrallongitudinal axis A which is collinear with their longitudinal axes.

The core airflow is compressed by the low pressure compressor 44 thenthe high pressure compressor 52, mixed and burned with fuel in thecombustor 56, then expanded over the high pressure turbine 54 and lowpressure turbine 46. The mid-turbine frame 58 includes airfoils 60 whichare in the core airflow path C. The turbines 46, 54 rotationally drivethe respective low speed spool 30 and high speed spool 32 in response tothe expansion. It will be appreciated that each of the positions of thefan section 22, compressor section 24, combustor section 26, turbinesection 28, and fan drive gear system 48 may be varied. For example,gear system 48 may be located aft of combustor section 26 or even aft ofturbine section 28, and fan section 22 may be positioned forward or aftof the location of gear system 48.

The engine 20 in one example is a high-bypass geared aircraft engine. Ina further example, the engine 20 bypass ratio is greater than about six(6), with an example embodiment being greater than about ten (10), thegeared architecture 48 is an epicyclic gear train, such as a planetarygear system or other gear system, with a gear reduction ratio of greaterthan about 2.3 and the low pressure turbine 46 has a pressure ratio thatis greater than about five. In one disclosed embodiment, the engine 20bypass ratio is greater than about ten (10:1), the fan diameter issignificantly larger than that of the low pressure compressor 44, andthe low pressure turbine 46 has a pressure ratio that is greater thanabout five 5:1. Low pressure turbine 46 pressure ratio is pressuremeasured prior to inlet of low pressure turbine 46 as related to thepressure at the outlet of the low pressure turbine 46 prior to anexhaust nozzle. The geared architecture 48 may be an epicycle geartrain, such as a planetary gear system or other gear system, with a gearreduction ratio of greater than about 2.3:1. It should be understood,however, that the above parameters are only exemplary of one embodimentof a geared architecture engine and that the present invention isapplicable to other gas turbine engines including direct driveturbofans.

A significant amount of thrust is provided by the bypass flow B due tothe high bypass ratio. The fan section 22 of the engine 20 is designedfor a particular flight condition—typically cruise at about 0.8 Mach andabout 35,000 feet (10.67 km). The flight condition of 0.8 Mach and35,000 ft (10.67 km), with the engine at its best fuel consumption—alsoknown as “bucket cruise Thrust Specific Fuel Consumption (‘TSFC’)”—isthe industry standard parameter of lbm of fuel being burned divided bylbf of thrust the engine produces at that minimum point. “Low fanpressure ratio” is the pressure ratio across the fan blade alone,without a Fan Exit Guide Vane (“FEGV”) system. The low fan pressureratio as disclosed herein according to one non-limiting embodiment isless than about 1.45. “Low corrected fan tip speed” is the actual fantip speed in ft/sec divided by an industry standard temperaturecorrection of [(Tram ° R)/(518.7° R)]0.5. The “Low corrected fan tipspeed” as disclosed herein according to one non-limiting embodiment isless than about 1150 ft/second (350 m/second).

The example gas turbine engine includes the fan 42 that comprises in onenon-limiting embodiment less than about twenty-six (26) fan blades. Inanother non-limiting embodiment, the fan section 22 includes less thanabout twenty (20) fan blades. Moreover, in one disclosed embodiment thelow pressure turbine 46 includes no more than about six (6) turbinerotors schematically indicated at 34. In another non-limiting exampleembodiment the low pressure turbine 46 includes about three (3) turbinerotors. A ratio between the number of fan blades 42 and the number oflow pressure turbine rotors is between about 3.3 and about 8.6. Theexample low pressure turbine 46 provides the driving power to rotate thefan section 22 and therefore the relationship between the number ofturbine rotors 34 in the low pressure turbine 46 and the number ofblades 42 in the fan section 22 disclose an example gas turbine engine20 with increased power transfer efficiency.

The disclosed example gas turbine engine 20 includes a control andhealth monitoring system 64 (generally referred to as system 64)utilized to monitor component performance and function. In this example,a sensing/control/identification device (SCID) 68A is located within asub-system component (SSC) 70. The SCID 68A communicates withelectromagnetic energy to a remote processing unit (RPU) 66 through apath comprised of a transmission path 78 and a path 62 within a SSC 70as best seen in FIG. 2. The path may also be extended along one or moreshielded paths 72 to remote SCIDs 68B in separate SSCs 74 (FIG. 2). Thisentire path (e.g., transmission path 78, path 62, and shielded paths 72)comprises a shielded electromagnetic network (SEN) 65. The RPU 66 maytransmit signals to a network 71 of the SCID 68A, 68B (FIG. 2) and/orreceive information indicative of current operation of the componentbeing monitored. The transmission media for any portion of the SEN 65may include solid, liquid or gaseous material. In this example, apressure internal to the SSC 70 is monitored and that informationtransmitted through the path 62 of the SEN 65 to the RPU 66 for use incontrolling engine operation or monitoring component health. However, itshould be understood that it is within the contemplation of thisdisclosure that the disclosed system 64 may be utilized to controland/or monitor any component function or characteristic of aturbomachine or aircraft component operation and/or other machines.

Prior control & diagnostic system architectures utilized in variousapplications include centralized system architecture in which theprocessing functions reside in an electronic control module. Redundancyto accommodate failures and continue system operation systems areprovided with dual channels with functionality replicated in bothcontrol channels. Actuator and sensor communication is accomplishedthrough analog wiring for power, command, position feedback, sensorexcitation and sensor signals. Cables and connections include shieldingto minimize effects caused by electromagnetic interference (EMI). Theuse of analog wiring and the required connections limits application andcapability of such systems due to the ability to locate wires,connectors and electronics in small and harsh environments thatexperience extremes in temperature, pressure, and/or vibration.

Referring to FIG. 2, system 64 includes SEN 65 installed near, in, or oneach of several SSCs 70A-C, as examples of the SSC 70 of FIG. 1. Each ofthe SSCs 70A-C may be an engine component, actuator or any other machinepart from which information and communication is performed formonitoring and/or control purposes. In this example, each of the SSCs70A-C includes a path 62 of the SEN 65 that is the primary means ofcommunicating with one or multiple features of the particular SSC 70A-Cor remotely located SSCs 74. The remotely located SSCs 74 may contain asingle or multiple electronic circuits or sensors configured tocommunicate over the SEN 65.

The RPU 66 sends and receives power and data to and from the SSCs 70A-Cand may also provide a communication link between different SSCs 70A-C.The RPU 66 may be located on equipment near other system components orlocated remotely as desired to meet application requirements.

A transmission path (TP) 78 between the RPU 66 and SSCs 70A-C is used tosend and receive data routed through the RPU 66 from a control module orother components. The TP 78 may utilize electrical wire, optic fiber,waveguide or any other electromagnetic communication including radiofrequency/microwave electromagnetic energy, visible or non-visiblelight. The interface between the TP 78 and SSC 70A-C transmits power andsignals received through the TP 78 to one or multiple SCIDs 68A in theexample SSC 70A.

The example SCIDs 68A, 68B may be radio-frequency identification (RFID)devices that include processing, memory and/or the ability to connect toconventional sensors or effectors such as solenoids or electro-hydraulicservo valves. The SSC 70A may contain radio frequency (R/F) antennas,magnetic devices or optic paths designed to be powered and/orcommunicate to from the TP 78 paths. The SSCs 70A-C may also useshielded paths 72 that can be configured as any type of electromagneticcommunication, including, for instance, a radio frequency, microwaves,magnetic or optic waveguide transmission to the SCIDs 68B located withinthe remotely located SSCs 74.

Shielding 84 within and around the SSC 70A is provided such thatelectromagnetic energy or light interference 85 with electromagneticsignals 86 (shown schematically as arrows) within the SSC 70A aremitigated. Moreover, the shielding 84 provides that the signals 86 areless likely to propagate into the environment outside the SSC 70A andenable unauthorized access to information. Similarly, remotely locatedSSCs 74 can each include respective shielding 76 to limit signalpropagation away from or into SSCs 74. In some embodiments, confinedelectromagnetic radiation is in the range 1-100 GHz. Electromagneticradiation can be more tightly confined around specific carrierfrequencies, such as 3-4.5 GHz, 24 GHz, 60 GHz, or 76-77 GHz as examplesin the microwave spectrum. A carrier frequency can transmit electricpower, as well as communicate information, to multiple SCIDs 68A, 68Busing various modulation and signaling techniques.

RFID, electromagnetic or optical devices implemented as the SCIDs 68A,68B can provide information indicative of a physical parameter, such aspressure, temperature, speed, proximity, vibration, identification,and/or other parameters used for identifying, monitoring or controllingcomponent operation. The SCIDs 68A, 68B may also include control devicessuch as a solenoid, switch or other physical actuation devices. Signalscommunicated over the TP 78 may employ techniques such as checksums,hash algorithms, shielding and/or encryption to mitigate cyber securitythreats and interference.

The disclosed system 64 containing the SEN 65 (e.g., transmission path78, path 62, and shielded paths 72) provides a communication linkbetween the RPU 66 and multiple SSCs 70A-C, 74. The shielding 84, 76 canbe provided along the transmission path 78 and for each SSC 70A-C and 74such that power and communication signals are shielded from outsideinterference, which may be caused by environmental electromagnetic oroptic interference. Moreover, the shielding 84, 76 prevents intentionalinterference 85 with communication at each component. Intentionalinterference 85 may take the form of unauthorized data capture, datainsertion, general disruption and/or any other action that degradessystem communication. Environmental sources of interference 85 mayoriginate from noise generated from proximate electrical systems inother components or machinery along with electrostatic fields, and/orany broadcast signals from transmitters or receivers. Additionally, pureenvironmental phenomena, such as cosmic radio frequency radiation,lightning or other atmospheric effects, could interfere with localelectromagnetic communications. Accordingly, the individualizedshielding 84, 76 for each of the SSCs 70A-C and 74 prevent the undesiredinterference with communication. The shielding 84, 76 may be applied toenclosed or semi-enclosed volumes that contain the SCIDs 68.

It should be appreciated that while the system 64 is explained by way ofexample with regard to a gas turbine engine 20, other machines andmachine designs can be modified to incorporate built-in shielding foreach monitored or controlled components to enable the use of a SEN. Forexample, the system 64 can be incorporated in a variety of harshenvironment machines, such as an elevator system, heating, ventilation,and air conditioning (HVAC) systems, manufacturing and processingequipment, a vehicle system, an environmental control system, and allthe like. The disclosed system 64 includes the SEN 65 that enablesconsistent communication with electromagnetic devices, such as theexample SCIDs 68A, 68B, and removes variables encountered withelectromagnetic communications such as distance between transmitters andreceiving devices, physical geometry in the field of transmission,control over transmission media such as air or fluids, control over airor fluid contamination through the use of filtering or isolation andknowledge of temperature and pressure.

The system 64 provides for localized transmission to SCIDs 68A, 68B suchthat power requirements are reduced. Localized transmission occurswithin a shielded volume of each SSC 70A-C, 74 that is designedspecifically to accommodate reliable electromagnetic transmission forthe application specific environment and configuration. Shielding oflocalized components is provided such that electromagnetic signals arecontained within the shielding 84 for a specific instance of the SSC70A-C. The system 64 therefore enables communication with one ormultiple SCIDs 68 simultaneously. The example RPU 66 enables sending andreceiving of power and data between several different SSCs 70A-C and 74.The RPU 66 may be located on the equipment near other system componentsor located away from the machinery for any number of reasons.

The system 64 provides for a reduction in cable and interconnectingsystems to reduce cost and increases reliability by reducing the numberof physical interconnections. Reductions in cable and connecting systemsfurther provides for a reduction in weight while enabling additionalredundancy without significantly increasing cost. Moreover, additionalsensors can be added without the need for additional wiring andconnections that provide for increased system accuracy and response.Finally, the embodiments enable a “plug-n-play” approach to add a newSCID, potentially without a requalification of the entire system butonly the new component; thereby greatly reducing qualification costs andtime.

The TP 78 between the RPU 66 and the SSCs 70A-C utilized to send andreceive data from other components may take multiple forms such aselectrical wire, optic fiber, radio frequency signals or energy withinthe visible or non-visible light spectrum. The numerous options for acommunication path of the TP 78 enable additional design flexibility.The TP 78 transfers energy to the SSC 70A-C such that one or multipleSCIDs 68A, 68B can be multiplexed over one TP 78 to the RPU 66.

SCIDs 68A, 68B can include RFID devices that may or may not includeprocessing, memory and/or the ability to connect to conventionalsensors. Radio frequency (R/F) antennas, magnetic devices or optic pathswithin the SSCs 70A-C may be designed to communicate with one ormultiple SCIDs 68A, 68B. Moreover, R/F, microwave, magnetic or opticwaveguide transmission paths 72 can be utilized to communicate withindividual electromagnetic devices remotely located from the SSC 70A-C.

Shielding 84, 76 within and around the SSC 70A-C, 74 substantiallyprevents electromagnetic energy or light interference with signals andalso makes it less likely that signals can propagate into thesurrounding environment to prevent unauthorized access to information.

According to embodiments, electromagnetic (EM) communication with thesystem 64 can be performed through multi-material andfunctional/structural components including, for instance, fuel, oil,engineered dielectrics and enclosed free spaces. By forming waveguidesthrough existing machine components and using electromagneticcommunication for one or more of the TP 78, path 62, and/or shieldedpaths 72, system contaminants and waveguide size for given frequenciescan be reduced.

In embodiments, existing components of the gas turbine engine 20 of FIG.1 can be used to act as waveguides filled with air, fluids or aspecifically implemented dielectric to transmit EM energy for writingand reading to/from EM devices in a Faraday cage protected environment.Use of existing structure can allow waveguide channels to be built in atthe time of manufacture by machining passages or additivelymanufacturing waveguide channels as communication paths. For example,communication paths can be built into the structure of SSCs 70A-C and 74to guide EM energy through each component. The SSCs 70A-C and 74 maycontain gas such as air at atmospheric pressure or any other level, orliquids such as oil or fuel. In any part of the system 64, a dielectricmay be employed to resist contamination or to reduce requirements forwaveguide dimensions.

Various machine components may also be used for transmission if theproper waveguide geometry is designed into the component, which can alsoprovide functional and structural aspects of the machine. Examples, suchas machine housings, fluid (including air) fill tubes, hydraulic lines,support frames and members, internal machine parts and moving parts thatcan be coupled to or shaped into waveguide geometry may also beincorporated in embodiments. As one example, FIGS. 2 and 3 depict aplurality of compressor vane segments 104 of the compressor section 24of FIG. 1 that incorporate one or more communication path 102 integrallyformed in/on a component of the gas turbine engine 20 of FIG. 1. Eachcommunication path 102 can route a portion of electromagnetic signalscommunicated from the TP 78 to one or more of the SCIDs 68 of FIG. 3.Each communication path 102 also provides a potentially alternate routein which the electromagnetic signal can be channeled in the event of aline or linkage failure, thereby building in inherent redundancy andsystem level robustness.

In the example of FIG. 3, a compressor vane segment 104 includes anarcuate outer vane platform segment 106 and an arcuate inner vaneplatform segment 108 radially spaced apart from each other. The arcuateouter vane platform segment 106 may form an outer portion and thearcuate inner vane platform segment 108 may form an inner portion to atleast partially define an annular compressor vane flow path.

Communication path 102 in a vane 112 can be formed during amanufacturing process to directly carry electromagnetic signaling of theTP 78 through a component of the gas turbine engine 20 of FIG. 1directly to a SCID 68 depicted in FIG. 3. Communication path 102 canalso terminate with SCIDs 68 to read pressures, temperatures or otherparameters at the end of the TP 78 or 72. Waveguide usage can enablevery low transmission losses such that the RPU 66 of FIG. 2 can bephysically located much further away from the SCIDs 68A, 68B of FIG. 2than conventional free space transmitting devices. Use of a dielectricin the waveguides can reduce the dimensional requirements for thewaveguides and resist contaminants, such as moisture, particles, gases,corrosion, and/or liquids that may increase transmission losses.Embodiments can use fluids in existing systems to act as a dielectric,particularly fluids with a dielectric constant that approaches or isbetter than free space. Thus, existing fuel or oil lines of the gasturbine engine 20 of FIG. 1 may be used as waveguides if they haveappropriate dielectric properties.

Further embodiments include allowing transition of EM energy from awaveguide into a free space environment. Some of the SSCs 70A-C, 74 ofFIG. 2 have multiple SCIDs 68A, 68B that reside in a protected Faradaycage (e.g., a shielded volume within shielding 84, 76) filled with airor other fluids. Transitioning energy from a waveguide to and from anopen cavity is required to prevent unwanted signal loss. Embodimentstransition EM energy from TP 78 into a free space environment containingeither air or a fluid within shielding 84 of SSC 70A of FIG. 2 using anexample waveguide 200 of FIG. 4. The waveguide 200 may be an embodimentof the TP 78 or the shielded path 72 of FIG. 2. In some embodiments, EMenergy transitions through multiple interfaces having differentenvironmental characteristics, such as waveguide 250 of FIG. 5 as afurther example of the shielded path 72 of FIG. 2. Waveguides 200, 250can connect multiple SCIDs 68 and may pass through existing components,for instance, in communication path 102 of FIG. 3, to facilitatetransmission of EM power and signaling between devices. The waveguides200, 250 may incorporate “T”s, “Y”s, splitters or other branching typesto facilitate a network topology.

EM energy may be confined to a waveguide, or alternatively can betransmitted through a combination of waveguide and free spacecommunications in a shielded environment, e.g., within shielding 84, 76of FIG. 2, to meet system requirements for signal attenuation anddisturbances. Waveguide 200 of FIG. 4 can include a waveguidetransmitter interface 202 that enables electromagnetic signaltransmission within a waveguide medium or electromagnetic window 204 ina guidance structure 206 to a waveguide transition interface 208. Thewaveguide transmitter interface 202 may be an EM energy emitter, and thewaveguide transition interface 208 may be operable to pass the EM energythrough shaping, an antenna structure, or an active structure to aconfined free space within shielding 84, 76 of FIG. 2. The waveguidemedium 204 can be a gas or liquid, such as air, oil, fuel, soliddielectric, or the like. In some embodiments, the waveguide medium 204is a dielectric. The guidance structure 206 can be a metal tube and maybe integrally formed on/within a component of the gas turbine engine 20of FIG. 1, such as communication path 102 of FIG. 3. In otherembodiments, the guidance structure 206 is an outer edge of a dielectricand need not include a metallic structure. Although depicted as a singlestraight path, it will be understood that the waveguide 200 can bend andbranch to reach multiple SCIDs 68A, 68B of FIG. 2. In other embodiments,the waveguide 200 may take the form of a planer stripline, or trace on aprinted circuit board.

Transitioning EM energy from a waveguide to and from cavities using TP78 and/or shielded paths 72 can present a challenge when SCIDs 68A, 68Bof FIG. 2 are located in higher temperature or pressure environments,especially in environments containing fuel, oil, flammable liquids orthe associate vapors. With further reference to FIG. 5, the waveguide250 enables transitioning of EM energy from a first environment 251 intoa second environment 253 with a higher temperature and/or higherpressure capable barrier against fluids or gasses. Waveguide 250 of FIG.5 can include a waveguide transmitter interface 252 that enableselectromagnetic signal transmission within a guidance structure 256 to awaveguide transition interface 258. The waveguide transmitter interface252 may be an EM energy emitter in the first environment 251. Thewaveguide transition interface 258 may be operable to pass the EM energythrough shaping, an antenna structure, or an active structure from afirst portion 260 of the waveguide 250 to a second portion 262 of thewaveguide 250. The first portion 260 of the waveguide 250 may have afirst waveguide medium 254 that is different from a second waveguidemedium 264 of the second portion 262. A transition window 266 can beincorporated in the waveguide transition interface 258 as a dielectricor thin metal EM window operable to pass a frequency range of interestbetween the first portion 260 and the second portion 262 of thewaveguide 250. The second portion 262 of the waveguide 250 can alsoinclude a secondary waveguide transition interface 268 in the secondenvironment 253. The secondary waveguide transition interface 268 canact as a seal to prevent different temperatures and/or pressures of thesecond environment 253 from directly contacting the first portion 260 ofthe waveguide 250. The first waveguide medium 254 and the secondwaveguide medium 264 can be different gasses or liquids, such as air,oil, fuel, or the like and may have different nominal pressures and/ortemperatures. In some embodiments, the first waveguide medium 254 and/orthe second waveguide medium 264 is a dielectric. The guidance structure256 can be a metal tube and may be integrally formed on/within acomponent of the gas turbine engine 20 of FIG. 1, such as communicationpath 102 of FIG. 3. The guidance structure may also contain more thanone waveguide transition interface 258 with a corresponding transitionwindow 266 for redundancy purposes. Although depicted as a singlestraight path, it will be understood that the waveguide 250 can bend, T,and branch to reach multiple SCIDs 68A, 68B of FIG. 2.

As mentioned above and for effective EM security, it is necessary thatthe EM system be closed to external EM radiation so as to preventhacking, incursion, or false command or sensing to occur.Simultaneously, it is necessary to prevent the disposition of thesensing and commands to be read by an external source. Thus, internal EMsignals must not radiate beyond the confines of the waveguide and theSEN 65. In addition, external EM must not penetrate into the waveguidesand the SEN 65.

In order to achieve this, metal based waveguides 78, 72 and/or metalbased shielding 84, 76 is provided. As mentioned above and in someembodiments, the metal based waveguides 78, 72 and/or metal basedshielding 84, 76 or portions thereof is provided by existing componentsof the gas turbine engine. These metal based waveguides 78, 72 andshielding 84, 76 shield against EM radiation and incursion. In oneembodiment, the thickness of the metal walls of the waveguides 78, 72and/or shielding 84, 76 are configured to attenuate EM radiation whetherit is external or internal to the SEN 65 including the waveguides 78,72. As such, the required skin depth for a particular EM shielding canbe calculated. Skin depth is a measure of how far electrical conductiontakes place in a conductor, and is a function of frequency.

For example, skin depth can be calculated by knowing these threevariables: the resistivity ρ of the conductor in Ohms/meter or Ω/m; thefrequency f in Hertz; and the absolute magnetic permeability μ of theconductor. In one embodiment of the present disclosure, the thickness ofthe metal of the waveguides 78, 72 and/or shielding 84, 76 is sufficientto provide approximately 10 skin depths. In another embodiment, themetal of the waveguides 78, 72 and/or shielding 84 is sufficient toprovide approximately 5 skin depths. Of course, various embodiments ofthe present disclosure contemplate skin depths greater or less than theaforementioned values and and/or nested ranges within the aforementionedvalues. Furthermore and in one embodiment, the thickness of the metal isgreater than the skin depth of the metal of the wave guide.

In addition and in an alternative embodiment, further EM shielding ispossible by encapsulating the sensing and transmission elements in Gaussshields thus diminishing significantly the likelihood of incursion.

Thus, the waveguides 78, 72 and/or shielding 84 may further includemetal layers or screens selected to attenuate the radiated emissionseither externally or internally in order to protect the SEN 65 fromsources of interference.

As mentioned above and to prevent EM energy incursion into or out of aEM network, it is necessary to encase a potential radiator or detectionsource in what is called a Gauss shield, sometimes called a Faradaycage. The structure is usually made of a conductor (including metal,conductive polymers, etc.) which is sometimes magnetic. The structureattenuates EM energy as described earlier according to what skin depthit presents to the radiation.

Components in control and health management systems typically areconnected to a centralized control & diagnostic system. As illustratedand discussed with respect to FIG. 2, an RPU may be remote from thecentral processor or it may perform all control and health managementprocessing for the machine. In other systems the RPU may only functionto communicate with the SCIDs and rely on another supervisory unit forsystem operation. An important aspect of health management requires thatinformation about the components of the system be used to assesscomponent health and predict when maintenance action will be needed.With current systems, processing and storage of component health residesin a centralized RPU. If components are changed, any knowledge ofcomponent history or condition moves only with the RPU.

With current systems, a component such as an actuator or sensor forexample, would not retain any information about their own service usageor current condition because they can be physically separated from theRPU. In other words, if the component (e.g., actuator or sensor) isremoved from the network and placed into another network any historicaldata associated with the component is lost as it has been typicallystored in the RPU which remains with the original network.

Referring now to FIG. 6 another embodiment of the present disclosure isillustrated. In this embodiment, a shielded electromagnetic device isused for component tracking in the secure network. In this embodiment,the shielded electromagnetic device is secured to the component suchthat if the component is removed from the SEN 65 and placed into anotherSEN 65 data particular to the component is not lost. Alternatively, ifthe RPU 66 of the SEN 65 is replaced, the shielded electromagneticdevice can communicate with and provide data to the new RPU 66 installedin the SEN 65. This embodiment allows tracking of components in thefield through the use of EM devices, wherein historical data of thecomponent the RFID tag is secured to is retained.

In this embodiment, electronics in the form of a RFID tag are providedin a control component such that memory devices in the electronics canstore information about the component. This information may include butis not limited to, identification of the component or part (e.g., serialno, manufacturing date, date of service, length of service, historicaldata, historical operational data, or any other information valuable tothe remote processing unit, etc.). The RPU electronics communicate withthe RFID tag as shown in FIG. 2.

Referring again to FIG. 6, a schematic illustration in accordance withan embodiment of the present disclosure is shown. FIG. 6 illustrates anRFID tag or shielded electromagnetic device such as a SCID 68A, 68B,which is also illustrated in at least FIG. 2. In this embodiment, EMenergy is employed to power and read devices such as sensors or othercontrol devices and including but not limited to the RFID tag. As willbe appreciated by those of skill in the art, whether a sensor or controldevice is wired or wireless, some form of power is required to obtain asensor reading. In this embodiment and by utilizing free space EM energythe RFID device illustrated in FIG. 6 may be powered with the EM energyit receives, which is internal to the shielded network or system.

In one non-limiting embodiment, use of the shielded transmission paths78, 72 in the form of waveguides (e.g., waveguides 200, 250) allows verylow transmission losses such that power sources (e.g., RPU 66 of EMdevices) can be physically located farther apart as compared toconventional free space transmitting devices. Further, suchconfigurations of the present disclosure can still deliver enough powerto energize the SCIDs 68A, 68B.

The SCID 68A, 68B depicted in FIG. 6 receives energy from an EMtransmitting source such as the RPU described herein. The SCID 68A, 68Bmay have a rectification and power conditioning module 300 configured torectify and condition power received from the EM transmitting source.

In addition to power rectification and conditioning, the SCID 68A, 68Bfurther includes a communication interface module 302 that is configuredfor communication with the EM transmitting source. That is, thecommunication interface module 302 is configured to receive and processinformation received in EM transmissions from the EM transmittingsource. The SCID 68A, 68B may also comprise a control module 304, thatmay contain a microcontroller, microprocessor, or Field ProgrammableGate Array, etc. that can be programmed to control and/or communicatewith different sensors depending on the application needs. The controlmodule 304 can read and write to a memory or storage module 306, such asinternal memory (e.g., volatile and/or non-volatile memory) of the SCID68A, 68B. The internal memory of the SCID 68A, 68B is independent of theremote processing unit. In other words, the internal memory 306 of theSCID 68A, 68B is capable of storing data relevant to its associatedcomponent, which may be provided to other processors of the network. Asmentioned above, this data may include but is not limited to,identification of the component or part (e.g., serial no, manufacturingdate, date of service, length of service, historical data, historicaloperational data, etc.). Still further and in the case of non-volatilememory this data is contained with the component as it isremoved/disconnected from the network. The memory 306 may includeidentification information associated the SCID 68A, 68B, programs and/orapplications to be executed by the control module 304, or other data,which as mentioned above may be component serial number, engine serialnumber, date, operating times, and multiple parameters accumulatedvalues for temperature, speed, pressure and vibration or otherenvironmental factors. The control module 304 is further configured toreceive input from an external sensor(s) 308 through the sensorinterface 310, which in one embodiment may be used to compile dataassociated with the component the SCID 68A, 68B is associated withand/or secured to. The external sensor 308 can provide a sensor inputthat is transmitted to the SCID 68A, 68B through the sensor interface310.

The SCID 68A, 68B has the ability to read sensor or sensors 308operatively connected through the sensor interface 310 to the SCID 68A,68B. Furthermore, the SCID 68A, 68B has the ability to write informationto and read information from the storage module 306.

Moreover, the SCID 68A, 68B has practical immunity from wireless cybersecurity attacks, EMI, etc. due to shielding 77 Faraday or otherwiseprovided about the SCID 68A, 68B. In one embodiment, the shielding 77 isseparately applied to or located about the SCID 68A, 68B. In otherwords, the SCID 68A, 68B itself does not initially have the requiredshielding.

As mentioned above, the characterization data or data contained inmemory 306 of the RFID tag or SCID 68A, 68B shown in FIG. 6 may include,but not be limited to, component serial number, engine serial number,date, operating times, and multiple parameters accumulated values fortemperature, speed, pressure and vibration or other environmentalfactors any one of which may be specific to the component the SCID 68A,68B is secured to.

Accordingly, and since the memory of the RFID tag 68A, 68B isindependent from the RPU, the RFID tag 68A, 68B provides the ability tostore fault information data for components if they need to be removedand replaced during maintenance actions. Still further, theinformational data relevant to the component is available should thecomponent be removed from the network and/or the RPU of the network isreplaced.

Although a single RFID tag 68A, 68B for use with a single component isillustrated in FIG. 6 it is, of course, understood that multiple RFIDtags 68A, 68B may be employed with various components in the system 64.Therefore, various embodiments of the present disclosure provide theability to characterize and/or track a single device or multiple devicesthat are grouped together in the same hardware component that may bephysically combined with the EM device. Moreover, the RFID tag or SCID68A, 68B is separately provided with the requisite shielding 77.

As such, shielding 77 around the RFID tag or SCID 68A, 68B shown in atleast FIG. 6 as a dashed line provides protection for the communicationsignals between the RPU and the electronics associated with eachcomponent. Through a protected transmission line or waveguide 72, 78 asshown in at least FIG. 2, the RPU communicates with the SCID 68A, 68B inorder to retrieve or store information. In other words, the shielding 77that surrounds the SCID 68A, 68B allows for or is configured to provideEM communication through the protected transmission path, line orwaveguide 78, 72 and/or path 62, which in one embodiment may be throughan opening in the shielding 77 that is connected to the transmissionpath, line or waveguide 78, 72 and/or path 62 at one end. This protectedtransmission path, line or waveguide 78, 72 and/or path 62 is alsooperatively coupled to the RPU in order to provide the required EMcommunication passage.

To prevent “hacking” of the network components, according to anembodiment, each of the nodes on the network has suitable shielding notonly so that command and control not be wrestled from the primarynetwork, but also so that the individual components do not serve asradiators and thus either interfere with the surrounding communicationsystems, or reveal itself to adversaries.

Thus, shielding 77 may employ a Gauss or Faraday shield, which mayinclude specific designs necessary to protect each node, which areapplicable to aerospace applications and its relevant environments,including: temperature, corrosion, level of radiation, etc.

In one non-limiting embodiment, the applied Gauss or Faraday shield 77of the RFID tag 68A, 68B, may be made of metals (e.g., aluminum, copper,stainless, titanium, magnetic stainless, or equivalents thereof),conductive polymers, or composites. In one embodiment, the Gauss orFaraday shield 77 of the RFID tag 68A, 68B, may be in the form of a meshor screen surrounding the RFID tag 68A, 68B.

In yet another embodiment, the Gauss or Faraday shield 77 of the RFIDtag 68A, 68B, may be in the form of a potting compound. In thisembodiment, the RFID tag 68A, 68B may protrude through an opening in astructural component of the system and the potting compound is locatedabout the RFID tag 68A, 68B in order to provide the requisite shielding.In yet another embodiment, the Gauss or Faraday shield 77 of the RFIDtag 68A, 68B, may be in the form of a hemisphere to enclose back side ofa node inserted into a waveguide 78, 72.

Moreover, various embodiments of the present disclosure allow for remoteinterrogation of information stored in the memory of the SCID 68A, 68Bfrom a distance greater than with conventional open air wirelesscommunication. These embodiments use EM energy harvested from the signalwithout using other power sources.

While the present disclosure has been described in detail in connectionwith only a limited number of embodiments, it should be readilyunderstood that the present disclosure is not limited to such disclosedembodiments. Rather, the present disclosure can be modified toincorporate any number of variations, alterations, substitutions orequivalent arrangements not heretofore described, but which arecommensurate with the spirit and scope of the present disclosure.Additionally, while various embodiments of the present disclosure havebeen described, it is to be understood that aspects of the presentdisclosure may include only some of the described embodiments.Accordingly, the present disclosure is not to be seen as limited by theforegoing description, but is only limited by the scope of the appendedclaims.

1. A system of a machine, the system comprising: a network of aplurality of sensing/control/identification devices distributedthroughout the machine, at least one of the plurality ofsensing/control/identification devices associated with at least onesub-system component of the machine and operable to communicate througha plurality of electromagnetic signals; shielding surrounding at leastone of the sensing/control/identification devices to contain theelectromagnetic signals proximate to the at least one sub-systemcomponent; and a remote processing unit operable to communicate with thenetwork of the sensing/control/identification devices through theelectromagnetic signals, wherein the at least one of the plurality ofsensing/control/identification devices has internal memory independentof the remote processing unit, the internal memory having historicaldata corresponding to the least one sub-system component.
 2. The systemas recited in claim 1, wherein the shielding further comprises a metalwaveguide, wherein the thickness of the metal of the waveguide isgreater than a skin depth of the metal of the waveguide.
 3. The systemas recited in claim 2, wherein the shielding is a Faraday shield.
 4. Thesystem as recited in claim 1, wherein the shielding preventselectromagnetic signals external to the network from reaching the leastone of the sensing/control/identification devices.
 5. The system asrecited in claim 1, wherein the shielding is a metal screen.
 6. Thesystem as recited in claim 1, wherein the at least one of thesensing/control/identification devices is a RFID tag powered by an EMtransmitting source.
 7. The system as recited in claim 7, wherein the EMtransmitting source is the remote processing unit.
 8. A system for a gasturbine engine, the system comprising: a network of a plurality ofsensing/control/identification devices distributed throughout the gasturbine engine, at least one of the sensing/control/identificationdevices associated with at least one sub-system component of the gasturbine engine and operable to communicate through a plurality ofelectromagnetic signals; and a remote processing unit operable tocommunicate with the network of the sensing/control/identificationdevices through the electromagnetic signals, wherein the at least one ofthe plurality of sensing/control/identification devices has internalmemory independent of the remote processing unit, the internal memoryhaving historical data corresponding to the least one sub-systemcomponent.
 9. The system as recited in claim 8, wherein the at least onesub-system component is part of at least one of a fan section, acompressor section, a combustor section and a turbine section of the gasturbine engine, and the at least one sub-system component contains aparameter of interest to a control and health monitoring system, whereinthe parameter of interest is one of a pressure, a temperature, a speed,a position, vibration and proximity or any other relevant physicallymeasurable parameter that is stored in the internal memory independentof the remote processing unit.
 10. The system as recited in claim 8,further comprising shielding surrounding the at least one of thesensing/control/identification devices to contain the electromagneticsignals proximate to the at least one sub-system component.
 11. Thesystem as recited in claim 9, wherein the shielding wherein theshielding further comprises a metal waveguide, wherein the thickness ofthe metal of the waveguide is greater than a skin depth of thewaveguide.
 12. The system as recited in claim 9, wherein the shieldingprevents electromagnetic signals external to the network from reachingthe least one of the sensing/control/identification devices.
 13. Thesystem as recited in claim 9, wherein the shielding is metal screen or aFaraday shield.
 14. The system as recited in claim 8, wherein the atleast one of the sensing/control/identification devices is a RFID tagpowered by an EM transmitting source.
 15. The system as recited in claim14, wherein the EM transmitting source is the remote processing unit.16. A method of tracking data relevant to a component of a gas turbineengine, the method comprising: securing a sensing/control/identificationdevice to a sub-system component of the gas turbine engine; shieldingthe sensing/control/identification device from external electromagneticsignals proximate to the sub-system component; storing data relevant tothe sub-system component in memory of the sensing/control/identificationdevice; and transmitting the data to a remote processing unit viaelectromagnetic signals through a waveguide.
 17. The method as recitedin claim 16, wherein the communication path comprises a waveguide. 18.The method as recited in claim 16, wherein the sub-system component ispart of at least one of a fan section, a compressor section, a combustorsection and a turbine section of the gas turbine engine, and thesub-system component contains a parameter of interest to a control andhealth monitoring system comprising the remote processing unit, whereinthe parameter of interest is one of a pressure, a temperature, a speed,a position, vibration and proximity or any other relevant physicallymeasurable parameter that is stored in the memory of thesensing/control/identification device.
 19. The method as recited inclaim 16, wherein the sensing/control/identification device is a RFIDtag powered by an EM transmitting source.
 20. The method as recited inclaim 19, wherein the EM transmitting source is the remote processingunit.